The present invention relates to a safety mechanism for a lighter, and more specifically a safety mechanism that obstructs the operation of the piezoelectric unit in the lighter to prevent ignition of fuel.
Some types of lighters typically include a piezoelectric unit, which when operated, produces sparks to ignite a stream of flammable gas. A conventional piezoelectric unit includes a plunger which is moveable within a main casting. The main casting includes an electrical ceramic element. When the plunger is pressed into the main casting, its bottom portion strikes the electrical ceramic element to generate an electric current. In a typical lighter, flammable gas is supplied from a chamber to a nozzle. The electric current produced by the piezoelectric unit is delivered to a position near the nozzle where it is emitted as a spark to ignite the gas that is streaming out of the nozzle.
The use of conventional lighters is relatively simple. In conventional lighters, for example, the plunger of the piezoelectric unit is connected to a trigger, a button, or some other actuating mechanism that can be manipulated by a user to press the plunger into the main casting of the piezoelectric unit. The simplicity of operation of conventional lighters is disadvantageous as it makes it easy for children to ignite the lighter thereby creating a risk of accidental fires. To reduce the risk of misuse by children, mechanisms have been incorporated in lighters to make their use more complicated. Often such mechanisms include a safety feature which must first be actuated before the lighter is ready to be used. A well known mechanism for preventing usage of a lighter by children involves a mechanism for obstructing the motion of the trigger to prevent ignition of the lighter. U.S. Pat. No. 6,135,762, for example, shows a lighter which includes a feature that engages the trigger to obstruct its motion. Such mechanisms work well. Generally, however, such safety mechanisms include a trigger mechanism having unique features. Thus, to take advantage of such safety mechanisms, the trigger mechanism of the lighter must be designed according to such unique features. That means that each commercial lighter must be customized to include the unique features. It is desirable to provide a safety mechanism that can be universally incorporated into all commercial lighters utilizing a piezoelectric unit, without regard to the configuration of the trigger itself.
It is an object of the present invention to provide a lighter safety mechanism that might be incorporated in any lighter which includes a piezoelectric ignition unit.
A lighter regardless of the purpose for which the lighter may be used and regardless of its shape and size, according to the present invention includes a universal safety mechanism for a piezoelectric lighter ignition unit. That mechanism has an ignition plunger that is selectively moveable within a main casting to generate a spark for igniting a stream of flammable gas, and some type of locking object or stop obstructs the movement of the plunger into the main casting to prevent ignition. Examples of stops may be any element that presents an obstacle, such as a rod, a spring, a latch etc.
In one preferred non-limiting embodiment, the plunger of the piezoelectric unit according to the present invention includes a notch on one side thereof. The notch has an open surface which is oriented transverse to the direction of motion of the plunger. The latch includes a stop portion which is selectively moveable to a position where it may oppose the transverse open surface in order to obstruct the motion of the plunger.
In a lighter safety mechanism according to the preferred embodiment, the latch includes an arm which is integral with the stop portion to form a unitary L-shaped latch. The arm portion extends from the interior of the housing of the lighter that houses the piezoelectric unit to the exterior of the housing where it may be manipulated by a user to selectively move the stop portion from a stop position where it opposes the transverse open surface to an open position away from the transverse open surface to allow the plunger to be pressed freely into the main casting. According to the preferred embodiment, the latch is spring-loaded so that it is returned to a position where its stop portion may oppose the transverse open surface when the user stops manipulating the arm. Alternative types of stops or obstacle elements share in common the movability between the stop and open plunger motion positions.